As I mentioned in my last newsletter, since 10.5.1, Leopard has been fairly stable. But a couple of computers I manage, especially servers, have run into some pretty dire problems with Leopard.
So I've been waiting for this with baited breath:
Leopard finally updated to 10.5.2
Basic info here, and there's a complete list of fixes here. But what I really want you to know is that, as with any major OS X update, you should download the combo update, rather than letter Software Update do the work for you. I promise, it does a much more thorough job, and keeps your Mac happy.
The 10.5.2 Combo Update can be found here. And the one for OS X Server, here. Just click the blue-underlined file size over on the right.
Macfixit.com, the go-to site for Mac troubleshooting, hasn't released any reports about 10.5.2. Please let me know if you have questions about the update.